I absolutely love to procrastinate and it's very important to me. Actually I am procrastinating by writing this comment right now. Allow me to explain:
When I program, or do math, it's very important to me to have a clear head; and I take procrastinating very seriously because I know if I don't do certain things then I will have a hard time concentrating when I sit down to work, and that will prevent me from going into "the zone", or achieving what some people call "flow".
There is such a huge difference between not only the amount of work I get down, but the quality of that work, when I am in the zone as opposed to when I am not; and procrastinating is sort of a ritual for me. I have to have a clean room, I have to have my desk nice and tidy, I have to have a glass of water, or a cup of coffee, in the same place on my desk that it always goes, I need to open my notebook to review my notes from the day before, and so on. Maybe I'm slightly OCD, but I do these things on purpose as part of a ritual to get into the zone.
If I have an urge to check HN, I log in and do it. Otherwise when I start working I have an awful nagging thought that won't go away saying "hey you know, there is probably something awesome on HN!" and the fact is I need that extra space in my brain to load up all the details of the code I am working on.
Then I load up my music playlist, put on my headphones, fire up my code editor, and the next thing I know it's 4 hours later and my stomach is growling because I have completely lost track of time. Guess what? Time to procrastinate again, otherwise productivity starts trailing off, and the quality of the work suffers.
Sometimes I keep coding anyway, but then I come back the next day and say to myself, "Jesus, what was I thinking when I wrote this crap! I wish I hadn't closed Eclipse before I went to bed, because now I can't ctrl-z out of this mess!" So it's actually a bad idea for me to keep programming when I start getting distracted by random things because then I have to waste a bunch of time the next time I sit down, just undoing a bunch of crap.
I love procrastinating, and I don't consider it a form of laziness at all, but just for a different reason.